Adjusted calcium conflict resolved? Differing effects on plasma total calcium of changes in plasma albumin after venous stasis or myocardial infarction.

Abstract

SUMMARY Others have challenged the concept of adjusting total plasma calcium for albumin concentration on the grounds that after the application of a tourniquet the increase in calcium for a given increase in albumin differs significantly between normal individuals. We have confirmed this finding.In contrast, we have found that after myocardial infarction the fall in calcium for a given fall in albumin does not differ significantly between patients. Thus the adjustment of calcium for albumin using a single equation remains valid in patients with changes in albumin due to disease.We recommend that for consistent results blood should be taken with the minimum of venous stasis even though the patient's calcium is to be adjusted for albumin.

Association of Admission Serum Calcium Levels and In-Hospital Mortality in Patients with Acute ST-Elevated Myocardial Infarction: An Eight-Year, Single-Center Study in China

“…The results of our study are consistent with the above study. Moreover, it has been well established that less than half of total serum calcium is protein bound, principally to albumin [20]. In the present study, although albumin level seemed to be significantly lower in hypocalcaemia group, all data were within a small zone and the normal range.…”

Accuracy of methods to estimate ionized and “corrected” serum calcium concentrations in critically ill multiple trauma patients receiving specialized nutrition support

“…Eighty-one patients were receiving enteral nutrition, 18 received parenteral nutrition, and 1 patient had transitional feeding with combined enteral and parenteral nutrition at the time of study. Patients were given a polymeric, fiber-containing, high-nitrogen enteral formula Methods that determine a "corrected" total serum calcium concentration Dent, 1962 17 TotCa Ϫ 0.675*(TotProt Ϫ 7.2) Parfitt, 1969 18 TotCa/(0.6 ϩ 0.0541*TotProt) Parfitt, 1974 19 TotCa/(0.6 ϩ 0.0541*TotProt) Husdan, 1973 43 TotCa/(0.6 ϩ 0.0515*TotProt) Christiansen, 1975 21 TotCa/(0.6 ϩ 0.05*TotProt) Kelly, 1976 22 (TotCa Ϫ 6)/(0.5*TotProt) Orrell, 1971 23 TotCa Ϫ 0.707*(Alb Ϫ 3.4) Berry, 1973 24 TotCa Ϫ 0.91*(Alb Ϫ 4.6) Payne, 1973 25 TotCa Ϫ (0.989*Alb) ϩ 4 Moore, 1970 26 TotCa Ϫ 4*((0.0019*Alb Ϫ (0.42*(Alb/473)*(7.42 Ϫ pH)) ϩ 0.0004*(TotProt Ϫ Alb) Ϫ (0.42*((TotProt Ϫ Alb)/250)*(7.42 Ϫ pH)))) Modified Orell 27 TotCa ϩ 0.8*(4 Ϫ Alb) Ryan, 1973 28 TotCa ϩ 0.72*(4 Ϫ Alb) Pain, 1975 29 TotCa ϩ (4 Ϫ Alb) Walker, 1979 30 TotCa ϩ 0.92*(4 Ϫ Alb) Thode, 1989 31 TotCa*2. 16,44 Derived from the nomogram AG, anion gap; Alb, serum albumin concentration (mg/dL), pH, arterial blood pH; TotCa, serum total calcium concentration (mg/dL); TotCO 2 , serum total carbon dioxide content; TotProt, serum total protein concentration (g/dL).…”

Fasting serum CGRP levels are related to calcium concentrations, but cannot be elevated by short-term calcium/vitamin D supplementation

“…Both CT and CGRP can lower blood calcium (Tippins et al, 1984;Zaidi et al, 1987), so elevated CT and CGRP may result in hypocalcemia in patients with acute MI. Secondly, two studies have found that both blood calcium and albumin are decreased in the period of acute MI, one of which has pointed out that the reasons for this change could be related to confinement to bed (Walker and Payne, 1979;Wiener, 1977). Furthermore, we have found a negative correlation between NT-proBNP and serum calcium, so we speculate that blood redistribution caused by the changes of cardiac function may also be an important reason.…”